The new 3.0-liter Duramax Diesel LZ0 we’ll see on the 2023 Chevy Silverado takes the first-generation LM2 diesel and makes key improvements for better performance with more horsepower and torque. In effect, General Motors has taken a good powertrain and made it much, much better.
And, um, hopefully, this new engine also fixes the long crank, slow start issue on the prior engine.
What’s not new: This engine is still an inline six-cylinder turbo. But what is new is the power — and it is a big improvement. GM says the new LZ0 Duramax Diesel will deliver 305 horsepower and 495 pound-feet of torque, which are 10% and 7.6% increases from the 2022 model year. The 2022 diesel delivered 277 horsepower and 460 pound-feet of torque.
GM was able to do this by using new steel pistons with a revised combustion bowl, retuned turbo compressor, new fuel injectors and improved temperature control features.
It will be available for the following 2023 Chevrolet Silverado trims: Custom Trail Boss, LT, RST, LT Trail Boss, LTZ and High Country. This new diesel engine will mated to the 10-speed automatic transmission like the older model.
There is no official word yet as to which GMC Sierra trims will get it or availability on the Chevy Tahoe, GMC Yukon and Cadillac Escalade.
Notably the press release leaves out any mention of fuel economy for the new 3.0-liter Duramax Diesel LZ0. While those figures will be released closer to launch, we have to imagine they will be similar to the prior LM2 engine.
For reference, the Duramax Diesel LM2 returns upwards of 31 MPG on the highway for 2WD models. Then for city and combined driving numbers, you’re looking at 23 and 26 MPG, respectively. This fuel economy drops significantly with 4WD models as the highway MPG goes from 31 to 26 and the city MPG from 22 to 23.
For the off-road models like the Trail Boss, fuel economy suffers even more, dropping to 23 MPG on the highway and 20 MPG in the city.
In our testing, we saw similar numbers to the estimated MPG number. However, the big stand outs were how good it pulled a camper and the impressive fuel economy numbers when towing — which were in the mid-teen range.
GM says the Duramax Diesel will continue to be assembled at the Flint Engine Operations, and it will be available on select trims of the 2023 Silverado 1500 by the end of 2022. Pricing hasn’t been announced, but the prior generation saw a $995 up-charge.
Taking an already beloved engine and improving it is a win-win proposition, and the 3.0-liter Duramax Diesel LZ0 is sure to be a fan favorite. Not only should it provide excellent fuel economy, but it will also likely be quick off the line, quiet and have plenty of passing power. Plus, if the previous generation is anything to go by, it’ll tow pretty darn well, too! The Duramax Diesel has been one of the biggest hits for GM’s powertrain department in recent memory, and we expect the trend to continue with this newest iteration.
As an owner of the LM2 I have put 57,000 miles on an AT4 which is similar to the trail boss and have averaged 26.5 miles per gallon
You wrote “This fuel economy drops significantly with 4WD models as the highway MPG goes from 31 to 26 and the city MPG from 22 to 23.”
Does this mean that the 4×4 models get significantly worse gas mileage compared to 2wd models even if they are driven with 2wd mode?
Yes. More drivetrain drag.